Prepare for React: Use Haste resolver for Web

In preparation for and as another early step in rewriting the Web
version of jitsi-meet using React, use Haste resolver which is able to
distinguish among platform-independent files, Web-specific and
mobile-specific ones.

Additionally, (1) make sure that Babel is capable of understanding React
files and (2) introduce React as a dependency.

The purpose is to repeatedly take small steps towards our goal and merge
them before they get in conflict with the separate ongoing advancement
of the Web version of jitsi-meet.

package.json

@@ -21,19 +21,21 @@
     "autosize": "^1.18.13",
     "bootstrap": "3.1.1",
     "events": "*",
+    "haste-resolver-webpack-plugin": "^0.2.2",
     "i18next": "3.4.4",
     "i18next-xhr-backend": "1.1.0",
-    "jquery-i18next": "1.1.0",
-    "json-loader": "0.5.4",
-    "jQuery-Impromptu": "trentrichardson/jQuery-Impromptu#v6.0.0",
     "jquery": "~2.1.1",
     "jquery-contextmenu": "*",
+    "jquery-i18next": "1.1.0",
+    "jQuery-Impromptu": "trentrichardson/jQuery-Impromptu#v6.0.0",
     "jquery-ui": "1.10.5",
+    "json-loader": "0.5.4",
     "jssha": "1.5.0",
     "jws": "*",
     "lib-jitsi-meet": "jitsi/lib-jitsi-meet",
     "postis": "^2.2.0",
     "react": "15.3.2",
+    "react-dom": "15.3.2",
     "react-native": "0.37.0",
     "react-native-vector-icons": "^2.0.3",
     "react-native-webrtc": "jitsi/react-native-webrtc",
@@ -49,9 +51,11 @@
   },
   "devDependencies": {
     "babel-core": "*",
-    "babel-loader": "*",
+    "babel-loader": "^6.2.8",
     "babel-polyfill": "*",
     "babel-preset-es2015": "6.14.0",
+    "babel-preset-react": "^6.16.0",
+    "babel-preset-stage-1": "^6.16.0",
     "clean-css": "*",
     "css-loader": "*",
     "eslint": ">=3",

webpack.config.js

@@ -2,6 +2,7 @@
 
 require('babel-polyfill'); // Define Object.assign() from ES6 in ES5.
 
+var HasteResolverPlugin = require('haste-resolver-webpack-plugin');
 var process = require('process');
 
 var aui_css = __dirname + '/node_modules/@atlassian/aui/dist/aui/css/';
@@ -16,16 +17,19 @@ var config = {
     devtool: 'source-map',
     module: {
         loaders: [{
-            // Transpile ES2015 (aka ES6) to ES5.
+            // Transpile ES2015 (aka ES6) to ES5. Accept the JSX syntax by React
+            // as well.
 
             exclude: __dirname + '/node_modules/',
             loader: 'babel',
             query: {
                 presets: [
-                    'es2015'
+                    'es2015',
+                    'react',
+                    'stage-1'
                 ]
             },
-            test: /\.js$/
+            test: /\.jsx?$/
         },{
             // Expose jquery as the globals $ and jQuery because it is expected
             // to be available in such a form by multiple jitsi-meet
@@ -83,6 +87,9 @@ var config = {
         path: __dirname + '/build',
         sourceMapFilename: '[name].' + (minimize ? 'min' : 'js') + '.map'
     },
+    plugins: [
+        new HasteResolverPlugin()
+    ],
     resolve: {
         alias: {
             aui: